Thermostat.



A. T. ZIEGLBR.

THERMUSTAT.

APPLIOATION FILED s152124, 1907.

906,357. f Patented neas, 1908.

l3 SHEETS-SHEET 1.

A. T. ZIEGLER.

' THERMOSTAT. APPLIoATIoN FILED sEPT.24, 1907'.

' Patented Dec. 8, 1908.

3 SHEETS-SHEET 2.

@mi h1 @aseo attocniisl f A. T. ZIEGLBR.

THERMOSTAT.

APPLICATION FILED SEPT. 24, 1907.

Patented Dec. 8, 1908.

3 SHEETS-SHEET 3.

wi h1 mozo' Aso y UNITED STATES PATENT oEEIoE.

ALFRED T. ZIEGLER, OF ALLEGHENY, PENNSYLVANIA.

THERMOSTAT.

the invention, has for one of its objects toprovide simple and efficient means for'automatically controlling the gas sup ly for that type of water heaters generally own and designated in the trade as instantaneous heaters. My invention aims to combine novel de'- vices forautomatically controlling a -gas valve, the principal device being 'a thermostat, the operation of which is adapted to close an electric circuit and release 'another device contrlling the as valve.

- Another characteristlc of the invention is the o eration of a safety plug, operating as a t ermostat, this safety `plug being employed to operate the gas valve, when the` ow of hot water is retarded, while the gas of the main burner or burners remains burnin thus ca the water to back up in the co d water suiy pipe.

. A furt er obycct of the invention is to prov ide a slow-acting switchto hold the gasvalve controlling circuit open for an appreciabletime, to permit the thermostatlc bars assuming their normal position after they are reheated biylffthe re-hghting of the pilot burner after t e gas-valve has been automatically closed.

With' these objects in view the invention consists of the mechanism and novel combination-of devices hereinafter more fully described and set forth inthe appended claims, in connection with the'aceompanyin drawingwhich form a part of this'speci cation.

the drawings: Figure' 1. is a view partly in -side elevation, part y brokenaway, and partly in section, of an instantaneous Water eater with my thermostat lapplied, thereto. 2 is a diagrammatic lview showing the electrical connections, and sho thethermostatic plug :ofthe lcold water pipe in section. Fig. 3 is a side .elevation ofv a ilot light burner showin vthe thermostat ars attached thereto. f 1g. 4fis a top plan view thereof. 5 is a srde elevation partly in.

section lof an` electrically` operatedgas con'- Specication of Letters Patent. Application sied september 2i, 19o?. serial No. 394,367.

owing is a' Patented Dec. 8, 1908.

trollin valve forming part of the invention, and, ig. 6 is a front elevation of the same with the shank of the valve handle in section. Fig. 7 is a vertical section on an enlarged switch being illustrated in its abnormal position, Fig. 8 is a vertical section on 'an enlarged scale ofthe thermostatic safetylug,

Fig. 9 is a horizontal sectional view o another form of slow-acting switch, and Fig. 10

is a-top plan view of the switch shown in the drawings the reference numeral 1 scale of one form of slow-moving switchV adapted for use with the improvement, the' designates a gas pipe surmounted by'` a.

burner 2, providing the pilot flame for an instantaneous water heater A of a well known t pe. Projecting from the pipe 1 is an ang e arm 3 carrying a head 3a to which are secured by bolts 4 two composite bars, each consisting of anl iron plate 5 and a brass plate 6. Each of the composite bars is provided with a contact point designated by the numerals 7 and 8 respectively. The contact 7 is connected by wire conductor 9 with a binding post 10, carried on a platform 10", suitably secured to the valve casing 11 of the valve 12, saidvalve controlling the gas suply to the. pipe 1 and also to the main burner of the water heater. The other contact 8 of the thermostat is connected by a conductor 13 to a switch 14, hereinafter described, thence'to a battery 15, and relay 16 operating in con'unction with a battery 16 and electric be e plug or valve 12 of the casing 11 is reduced, as at 12a and provided with a toothed sector 19, ksaid toothed sector being secured to the reduced end 12a of the plug or valve 12 by screws 21 or similar fastening means. The toothed sector 19 carries a handle 18, whereby the plug or valve 12 can be manually rotated or manipulated. Flat springs 50` bear upon the sector 1 9, thus preventing the plug or valve 12 from binding 1n the casing 11. Surrounding' the reduced end 12% of the valve or plug 12 is a coilband sp n11g20 havingits one end secured to the reduced 16a,`and to a binding post 17 on therplatform 10a.

end 12a of the plug or valve 12,1 and its other A. end secured to a post` lbcarried by the lat-A form 103.* 'i sprmg`20 is employ for automaticallyv rotating the valve or p1ug f 1 2 inl onedirection, when the tensionoflthe SPIDg Whih" has. been" Previously woiis .y released.' The plug'I2 carries a stop 51 arranged to enga e against pin 52 on the platform a after t e plug or valve 12 has made one quarter of a revolution.

Carried by the platform 10a are brackets 24 and 24a and between these brackets are arranged two electro -magnets 25. Pivotally secured between lugs 26 depending from the bracket 24 is an armature 27 provided with a handle 28, whereby the armature can be manually manipulated.

-Suitably supported in front of the sector 19 behind one of the electro-magnets is a movable rod 23 having one end projecting through an opening in the bracket 24 to be struck by the armature 27. The opposite end of the rod engages the pawl 22 pivotally mounted upon the platform 10aL by a post 22a. This pawl is normall held in engagement with the teeth of tlie sector 19 by a spring 22b attached to post 53 on platform 10a. To normally hold the rod 23 in engagement with the pawl 22, I provide said rod with a collar 23, and inter ose a coil spring 23b between said collar an the bracket 24, said spring encircling said rod. It will of course be understood that this spring is weaker than the spring 22", and is principally used to hold the rod 23 in such a position that the protruding end thereof can be struck a sudden and hammer-like blow by the armature. Besides being used for this purpose it relieves the armature 27 of the weight of the rod 23, consequently reducing the work of the armature 27.

The operation of the mechanism as thus far described is as follows: When the flame of the pilot burner 2 is accidentally blown out or extinguished, the temperature of the com osite thermostat bars is reduced, causing t em to contract, thus bringing'the contact points 7 and 8 together, to close an electi'ic circuit through the wire conductors 9 and 13, and the heavy battery 15 to energize the electro-magnets 25. When these magnets are energized' the armature 27 is attracted and strikes the protruding end of the rod 23, releasing the pawl 22 from its enga ement with the sector 19 and permitting t e previously wound spring 20 to partially rotate the valve or lug 12 and shut off the flow of gas to the p ot and main burner. To counterbalance the weight'of armature 27,

`when the valve is mounted in a vertical position, I employ a spi'in 25, (see Fig. 6 the tension of said spring ein such as to'leave the armature a sufficient 'stance from the electro-magnets to insure a stroke and blow upon rod 23 when the armature is attracted.

When .the plug or valve 12 is operated as above described, the electric circuit is through the relay 16, which attracts the armature 16c thereof and com letes the circuit through the battery 16b an the bell 16, sounding an audible signal. To prevent this bell 16a from continuously ringing, I immediately break the electric circuit 4after the valve or plug 12' has been moved. This is accomplished by mounting an insulated contact arm 19a upon the latform 10a, said arm enaging the smoot edge of the sector 19. he arm 19a is connected to one of the electro-ma nets by a wire 19h, and when the spring eld sector 19 is released, the circuit is immediately broken, upon the sector 19 traveling out of the path of the arm 19, breaking the contact between said arm and said sector. This only permits the audible signal 16a to sound for a few seconds, the spring 16d of the armature 16c of the relay 16 immediately withdrawing said armature when the circuit is broken. If for any reason the plug or valve 12 should fail to operate after contacts 7 and 8 are closed, the audible signal 16a will be sounded until the sector 19 is rotated manually or the slow-actin switch o erated and the pilot burner re ighted. ow, to permit of the thermostatic bars assuming t ieir normal position after they are re-heatedby the re-lighting of the ilot burner, requires the ein loyment of a s owacting switch to o en t e gas-valve circuit. Otherwise, when t e sector 19 is returned to its normal position, a circuit can be immediately set up, that would continuously sound the audible signal 16a and energize the electro-magnets 25. I prevent this by a switch, and have illustrated two forms which will be presently described.

In the distribution of hot water from a -water heater, it sometimes occurs that the circulation is retarded while the main burner or burners remain lighted, thus causing the 'backing u of the water and generation of steam wit the liability of causing an explosion or burning up of the pipes. To uard against this, I provide the cold water pipe 29 with a T-couplin 30 within which is a safety plug 31 of nove construction. The safety plug 31 is hollow and is threaded to screw into the coupling 30.y It is preferably formed of brass or an alloy and contains a copper tube 32, which is-interiorly lined with a soluble4 insulating material 32, as rosin. Centrally disposed within the interiorly lined copper tube 32 is a depending co per rod 33 depending from an insulated binding post 34 arranged in the top of the copper tube 32. The tube is illed with mercury and the plug 3,1 is (provided with a binding post 36, connecte by a conductor 37 with the battery circuit wire 9 heretofore referred to. The bindinglpost 34 is connected by a conductor 38 wit the battery circuit conductor 13. When the hot water backs up in the supply pipe 29, the soluble insulating lining 32a of the tube 32 is immediately melted by the hot water, allowing the mercury in the tube 32 to come in contact with the walls of-said tube, thus completing an electric circuit through saidvtube, plug 31, conductor 37 to the magnets 25, conductor 38 to rod 33, this circuit closing the gas valve 12.

Referring now to the slow-acting switch illustrated in the drawings, reference will first be had to the form shown in Fig. 7. The numeral 39 designates a cylinder provided with a binding post 40 and with perforated lugs 41 and 42 to adapt the cylinder to be attached to a suitable support. The lower end -of the cylinder 39 is formed with a threaded o ening 43 closed by a screw-plu 44, formedP with a lon itudinally dis ose groove, this plug contrling and regu ating the piston 45. Above the piston 45 is a (spring47 which bears against an insulation isk 48a through which the piston rod 46 extends. Upon this disk is secured a metallic contact ring 48b having a binding post 48e to which the conductor 13 is connected, the other battery conductor 13a being connected to the binding post 40 of the cylinder 39.

Near the upper end of the piston rod 46 is a collar 46*L adapted to contact with the `metallic ring 48b and establish a circuit between the wire conductors 13 and 13a. When the piston rod 46 is elevated, the spring 47 is placed under tension and upon t e rod being released, the spring 47 radually forces the-piston 45 downward, t e descent of the piston being regulated by the screw-plug 44. It will thus be observed that the slow-acting switch as described acts functionally as a dash-pot to insure a slow closing of the circuit, thus giving the thermostatic bars sufficient time to expand and assume their normal position before closing the circuit.

In lieu of the switch above described, 'I can employ a clock-work switch as shown in Figs.` 9 and 10. This switch comprises a winding arbor 55 having a conventional form of main spring 56. Upon the winding arbor 55 is a pin wheel 57 meshing with a toothed wheel 58, carried by a shaft 59 jour-` naled in the frame of the switch. The toothed wheel 58 is preferably three times as large as the pin wheel 57, whereby it will require three revolutions of the in wheel 57 to rotate the wheel 58 one comp ete revolution. The shaft 59 adjacent to the wheel 58 carries an insulated collar 61 having a screw 62 adapted to engage with'the arm 54 carried by the projection 63 of one of the frames 60. The wheel 58 also carries a pin 64 adapted to engage with the arm 65 carried by one of the frames 60. In operation, the winding arbor 55 is rotated until the pin 64 engages the armf65, this movement of the winding arbor placing the spring 56 under tension, and moving the screw 62 out of contact with the arm 54. Immediately 'upon the winding arbor 55 being released, the wheel 58 makes a complete revolution, the pin 64 engaging the opposite side of the arm 65, and the screw 62 making contact with the arm 54.

To gradually retard the movement of the winding arbor 55 I use a number of gears 52a for operating a fan wheel 53a. This clock movement switch is electrically connected to the battery circuit and is adapted to serve the same function as thev switch illustrated in Fig. 7 of the drawings, that is, to keep the circuit open until the thermostatic bars have assumed4 their normal position after the pilot burner is re-lighted.

The type of instantaneous heater to which I have shown the device attached is of al well known form in which the o ening of the hot water ffaucet C causes the inow of cold water to act on the thermostat D and open the gas controlling valve E so as to admit gas to the burner B where it is ignited by the pilot light flame to heat the water in the water heating coils F in a manner well known in the art.

Having now described my invention, what I claim as new, is

1. The combination with a Water heater supply pipe, and a gas valve, of a safety plugl lining of rosin or like soluble material, and

containing mercury, a binding post carried by said tube, a copper rod sus ended from said binding ost, and electrica connections between sai binding post and said plug valve.

3. In combination with a water heater having a cold water inlet pi e, la gas burner for the heater, a gas lsuptpvpipe for said burner, and a pilot light urner connected with said gas supply pipe, of a thermostat su ported above said p1lot li ht burner, a sa ety plug disposed in the co d water in let pi e, an electrically operated controlhn va ve disposed in said gas supply ipe, an electrical connections between sai gas controlling valve, and said thermostat, substantially as described.

4.' In combination with a hot water heater having a cold waterinlet ipe, a gas burner for sald heater, a gas supp y pipe'connected with said burner, and a ilot light burner connected to said gas supp y pipe, of a thermostat supported in close proximity to the pilot light burner, a safety4 plug disposed 1n the cold water inward ipe, e ectrical connections between the u and thermostat, an electrically operate va ve disposed in the gas supply ipe, and electrical connectlons between said) valve and said thermostat, substantially as described.

In combination with a hot water heater having a cold water inlet pipe, a burner for said heater, a gas supply pipe for said burner and a pilot light burner connected with said gas supply pipe, of a thermostat supported in close proximity to said pilot light burner, an electrically actuated valve in the gas supply pipe, electrical connections between the thermostat and said valve, and means for cushioning the movement of said valve when the same is electrically actuated.

6. In combination with a water heater having a cold water inlet pipe, a gas burner for said heater7 a gas supply pipe for said burner and a pilot light burner connected to l 15 said gas supply pipe, of a thermostat supported in close proximity to the pilot light urner, a safety tube dis osed in the cold water inlet pipe, electrica connections between said safety tube and said thermostat, an electrically actuated valve disposed in the gas supply pipe, electrical connections between said thermostat and said valve, and means for cushioning the movement of the valve when electrically actuated.

In testimony whereof I aix my signature in the presence of two witnesses.

ALFRED T. ZIEGLER. Witnesses:

K. H. BUTLER, MAX H. SRoLovITz. 

